Is there a way to change the username on the forum?

I didn't see any option to change name in my profile. I guess the answer is no. Do you have any specific reasons for the name change? Did you use the Koodo login credential or a Facebook account to sign into the forum?

I have a domain, so I’m used to come up with an email address on the spot (using unique addresses for different purposes, helps me organize them).

So when asked, I used koodo@<mydomain>, forgetting that several years ago I used that address for my daughter’s account (no longer active because she ported out).

So when I (unknowingly) re-used it, it came with the previous username.  I can live with it, but would prefer to change it if at all possible.

Only rep who had admin right can do a name change in the forum. 

If it wasn't important,I recommend you keep it as it is. Older posts (more than 2,3 year) normally got archived anyway.